Focal distance of human eyes is from 10 cm to infinity, so the human eyes cannot see any objects within a distance of 10 cm. In order for the human eyes to clearly see the contents displayed by the display device which is very close to the eyes, there are a lot of solutions in the field of glasses displays.
The glasses display products at present mainly comprise transmissive type and non-transmissive type. The transmissive type glasses display allows ambient light to pass through the glasses to enter human eyes, so as to integrate the virtual images be displayed with the outside landscape.
The images displayed by the glasses display products available in the market are all in the same virtual image plane, so the function of displaying virtual images at different distances simultaneously cannot be achieved.
One of patent documents in the prior art discloses that a glasses display which is made by zooming lens scanning method can display virtual images at different distances at different times. When the scanning speed is very fast and within the time interval which the human eyes cannot distinguish, it can be considered to realize displaying the virtual images at different distances simultaneously. However, this solution needs to adopt lens of which curvature can be controlled by voltage, so the structure is complicated, and still not really realize that the virtual images can be displayed at different distances simultaneously.
The largest view angle of the human eyes is around 120°, but the angle range displayed by the existing glasses display is limited by its optical structure, and it is usually only around 50°. Therefore, the experience on immersive visual is poor.
Based on the glasses display products and their shortcomings above, in order to develop a glasses display which can present virtual images at different distances simultaneously, the present invention provide a “spatial focal field type glasses display”.